1. Field of the Invention
The present invention relates to a sighting device for telescopes having inclined viewing. More particularly, the present invention relates to providing telescopes having inclined optic axes, i.e. inclined axes of sight, with sighting devices fastened to telescope housings for aiming the telescopes.
2. Description of the Related Technology
Since telescopes have small fields of vision, i.e., fields of view, particularly at high magnification, some users have difficulties aiming telescopes to view objects visible with the naked eye.
WO 96/26415 discloses a telescope with inclined viewing wherein a frame-shaped sighting device fastened to a portion of the telescope housing is provided above the eyepiece. For many users, who have no problems bringing objects within the fields of view of a telescope, having a sighting device on the telescope is only bothersome. Also, finding objects with known sighting devices leaves things to be desired.
An object of the invention is to provide a sighting device that makes it substantially easier to find objects to be viewed with the telescope by users who have problems aiming telescopes.
A further object of the invention is to provide a sighting device that can readily be removed from telescope housings by users without such problems.
In the inventive telescope, the sighting device of the invention is formed for easy insertion on and removal from the telescope housing. The user can thus mount and use the sighting device or remove it from the telescope housing at will. The sighting device is preferably mounted to be disposed adjacent and beside the eyepiece tube.
The sighting device of the invention has a line of sight parallel to the portion of the axis of sight of the telescope for viewing distant objects. The sight can be formed for example by a notch and bead, or as a strip or tube parallel to the portion of the telescope axis of sight for viewing distant objects. The sighting length can be for example 2 to 10 centimeters. If the sighting device used is a tube or optionally two spaced-apart rings, the interior diameters for example, can be 2 to 5 millimeters. Likewise, the sighting device can be formed by an optical aiming device, i.e. a telescopic finder with lower magnification than the primary telescope and a large field of vision.
The sighting device of the invention can be used for monocular or binocular telescopes.
A recess for inserting a mounting projection from the sighting device is preferably provided on the side, i.e. on the right or left, of the telescope housing. The mounting is preferably made along the inclined portion of the telescope housing. Since the sighting device is disposed on the side of the telescope housing, the mounting projection can be of a short and stable form. Further, the recess into which the mounting projection is inserted is preferably provided from a front wall portion of the inclined housing, i.e. the front wall surrounding the opening into which an eyepiece tube is inserted. It is also possible to provide a recess for inserting the sighting device mounting projection on the eyepiece tube.
It is especially preferred to provide the recess for inserting the sighting device mounting projection between the inclined housing portion and an eyepiece tube, such that the recess extends as a groove from the front wall along the inside of the inclined housing portion. Such a groove for the recess is easily produced.
To improve fixations for the mounting of the sighting devices, the mountings preferably have a bearing surface portion along the mounting projection for the sighting device that extends over the front wall of the inclined housing portion when the mounting projection has been inserted into the recess. Additionally, it is advantageous to provide the mounting projection with a concave surface on the side facing the eyepiece tube so that this portion of the mounting projection lies against the eyepiece tube.
The sighting device and the mounting projection are preferably formed integrally, in particular as a plastic part. For example, they can be an injection molded part.